The present disclosure relates to display technology, and more particularly, to a low temperature poly-silicon (LTPS) thin film transistor (TFT) array substrate and a method of producing the LTPS TFT array substrate.
In the manufacturing field of display screens, the low temperature poly-silicon (LTPS) technology is increasingly favored by manufacturers of cellphones, flat screens, and so on owing to the features of the LTPS technology such as low production costs and high electron mobility.
In the LTPS technology of the related art, a lot of films with a complex film structure are necessary so a lot of exposure with a lot of masks is required in the LTPS process. FIG. 1 illustrates the structure of a TFT film formed using the LTPS technology of the related art. The structure of the TFT film includes a glass substrate 100, a light shielding layer 101, a buffer layer 102, a poly-silicon layer 103, a gate insulating layer 104, a gate line 105, an interlayer insulating layer 106, a source electrode 108, and a drain electrode 109. The light shielding layer 101 is disposed on the glass substrate 100. The buffer layer 102 is disposed on the glass substrate 100 and the light shielding layer 101. The poly-silicon layer 103 is disposed on the buffer layer 102. The gate insulating layer 104 is disposed on the poly-silicon layer 103 and the buffer layer 102. The gate line 105 is disposed on the gate insulating layer 104. The interlayer insulating layer 106 is disposed on the gate line 105 and the gate insulating layer 104. The source electrode 108 is disposed on the interlayer insulating layer 106 and connected to the poly-silicon layer 103 through a source hole. The drain electrode 109 is disposed on the interlayer insulating layer 106 and connected to the poly-silicon layer 103 through a drain hole. FIG. 2 is a flowchart of the main process of forming the TFT film structure as illustrated in FIG. 1. According to this flowchart, it is necessary to use six or more masks to fabricate the TFT film structure as illustrated in FIG. 1. In order to solve the problem that the production costs are a little high due to too many masks used in the manufacturing process of the LTPS TFT device, major manufacturers are seeking ways to reduce the number of masks intended to be used in the manufacturing process.